bpo-40275: Move transient_internet from test.support to socket_helper (GH-19711)

14 files changed, 145 insertions, 137 deletions

diff --git a/Lib/test/support/__init__.py b/Lib/test/support/__init__.py
index ee5882f237..bd2157496f 100644
--- a/Lib/test/support/__init__.py
+++ b/Lib/test/support/__init__.py
@@ -78,7 +78,7 @@ __all__ = [
     "requires_linux_version", "requires_mac_ver",
     "check_syntax_error", "check_syntax_warning",
     "TransientResource", "time_out", "socket_peer_reset", "ioerror_peer_reset",
-    "transient_internet", "BasicTestRunner", "run_unittest", "run_doctest",
+    "BasicTestRunner", "run_unittest", "run_doctest",
     "skip_unless_symlink", "requires_gzip", "requires_bz2", "requires_lzma",
     "bigmemtest", "bigaddrspacetest", "cpython_only", "get_attribute",
     "requires_IEEE_754", "skip_unless_xattr", "requires_zlib",
@@ -144,8 +144,6 @@ SHORT_TIMEOUT = 30.0
 # option.
 LONG_TIMEOUT = 5 * 60.0
 
-_NOT_SET = object()
-
 
 class Error(Exception):
     """Base class for regression test exceptions."""
@@ -1387,90 +1385,6 @@ ioerror_peer_reset = TransientResource(OSError, errno=errno.ECONNRESET)
 
 
 @contextlib.contextmanager
-def transient_internet(resource_name, *, timeout=_NOT_SET, errnos=()):
-    """Return a context manager that raises ResourceDenied when various issues
-    with the Internet connection manifest themselves as exceptions."""
-    import socket
-    import nntplib
-    import urllib.error
-    if timeout is _NOT_SET:
-        timeout = INTERNET_TIMEOUT
-
-    default_errnos = [
-        ('ECONNREFUSED', 111),
-        ('ECONNRESET', 104),
-        ('EHOSTUNREACH', 113),
-        ('ENETUNREACH', 101),
-        ('ETIMEDOUT', 110),
-        # socket.create_connection() fails randomly with
-        # EADDRNOTAVAIL on Travis CI.
-        ('EADDRNOTAVAIL', 99),
-    ]
-    default_gai_errnos = [
-        ('EAI_AGAIN', -3),
-        ('EAI_FAIL', -4),
-        ('EAI_NONAME', -2),
-        ('EAI_NODATA', -5),
-        # Encountered when trying to resolve IPv6-only hostnames
-        ('WSANO_DATA', 11004),
-    ]
-
-    denied = ResourceDenied("Resource %r is not available" % resource_name)
-    captured_errnos = errnos
-    gai_errnos = []
-    if not captured_errnos:
-        captured_errnos = [getattr(errno, name, num)
-                           for (name, num) in default_errnos]
-        gai_errnos = [getattr(socket, name, num)
-                      for (name, num) in default_gai_errnos]
-
-    def filter_error(err):
-        n = getattr(err, 'errno', None)
-        if (isinstance(err, socket.timeout) or
-            (isinstance(err, socket.gaierror) and n in gai_errnos) or
-            (isinstance(err, urllib.error.HTTPError) and
-             500 <= err.code <= 599) or
-            (isinstance(err, urllib.error.URLError) and
-                 (("ConnectionRefusedError" in err.reason) or
-                  ("TimeoutError" in err.reason) or
-                  ("EOFError" in err.reason))) or
-            n in captured_errnos):
-            if not verbose:
-                sys.stderr.write(denied.args[0] + "\n")
-            raise denied from err
-
-    old_timeout = socket.getdefaulttimeout()
-    try:
-        if timeout is not None:
-            socket.setdefaulttimeout(timeout)
-        yield
-    except nntplib.NNTPTemporaryError as err:
-        if verbose:
-            sys.stderr.write(denied.args[0] + "\n")
-        raise denied from err
-    except OSError as err:
-        # urllib can wrap original socket errors multiple times (!), we must
-        # unwrap to get at the original error.
-        while True:
-            a = err.args
-            if len(a) >= 1 and isinstance(a[0], OSError):
-                err = a[0]
-            # The error can also be wrapped as args[1]:
-            #    except socket.error as msg:
-            #        raise OSError('socket error', msg).with_traceback(sys.exc_info()[2])
-            elif len(a) >= 2 and isinstance(a[1], OSError):
-                err = a[1]
-            else:
-                break
-        filter_error(err)
-        raise
-    # XXX should we catch generic exceptions and look for their
-    # __cause__ or __context__?
-    finally:
-        socket.setdefaulttimeout(old_timeout)
-
-
-@contextlib.contextmanager
 def captured_output(stream_name):
     """Return a context manager used by captured_stdout/stdin/stderr
     that temporarily replaces the sys stream *stream_name* with a StringIO."""
diff --git a/Lib/test/support/socket_helper.py b/Lib/test/support/socket_helper.py
index 5f4a7f19a3..b09c248cfc 100644
--- a/Lib/test/support/socket_helper.py
+++ b/Lib/test/support/socket_helper.py
@@ -1,7 +1,11 @@
+import contextlib
 import errno
 import socket
 import unittest
 
+from .. import support
+
+
 HOST = "localhost"
 HOSTv4 = "127.0.0.1"
 HOSTv6 = "::1"
@@ -175,3 +179,88 @@ def get_socket_conn_refused_errs():
     if not IPV6_ENABLED:
         errors.append(errno.EAFNOSUPPORT)
     return errors
+
+
+_NOT_SET = object()
+
+@contextlib.contextmanager
+def transient_internet(resource_name, *, timeout=_NOT_SET, errnos=()):
+    """Return a context manager that raises ResourceDenied when various issues
+    with the Internet connection manifest themselves as exceptions."""
+    import nntplib
+    import urllib.error
+    if timeout is _NOT_SET:
+        timeout = support.INTERNET_TIMEOUT
+
+    default_errnos = [
+        ('ECONNREFUSED', 111),
+        ('ECONNRESET', 104),
+        ('EHOSTUNREACH', 113),
+        ('ENETUNREACH', 101),
+        ('ETIMEDOUT', 110),
+        # socket.create_connection() fails randomly with
+        # EADDRNOTAVAIL on Travis CI.
+        ('EADDRNOTAVAIL', 99),
+    ]
+    default_gai_errnos = [
+        ('EAI_AGAIN', -3),
+        ('EAI_FAIL', -4),
+        ('EAI_NONAME', -2),
+        ('EAI_NODATA', -5),
+        # Encountered when trying to resolve IPv6-only hostnames
+        ('WSANO_DATA', 11004),
+    ]
+
+    denied = support.ResourceDenied("Resource %r is not available" % resource_name)
+    captured_errnos = errnos
+    gai_errnos = []
+    if not captured_errnos:
+        captured_errnos = [getattr(errno, name, num)
+                           for (name, num) in default_errnos]
+        gai_errnos = [getattr(socket, name, num)
+                      for (name, num) in default_gai_errnos]
+
+    def filter_error(err):
+        n = getattr(err, 'errno', None)
+        if (isinstance(err, socket.timeout) or
+            (isinstance(err, socket.gaierror) and n in gai_errnos) or
+            (isinstance(err, urllib.error.HTTPError) and
+             500 <= err.code <= 599) or
+            (isinstance(err, urllib.error.URLError) and
+                 (("ConnectionRefusedError" in err.reason) or
+                  ("TimeoutError" in err.reason) or
+                  ("EOFError" in err.reason))) or
+            n in captured_errnos):
+            if not support.verbose:
+                sys.stderr.write(denied.args[0] + "\n")
+            raise denied from err
+
+    old_timeout = socket.getdefaulttimeout()
+    try:
+        if timeout is not None:
+            socket.setdefaulttimeout(timeout)
+        yield
+    except nntplib.NNTPTemporaryError as err:
+        if support.verbose:
+            sys.stderr.write(denied.args[0] + "\n")
+        raise denied from err
+    except OSError as err:
+        # urllib can wrap original socket errors multiple times (!), we must
+        # unwrap to get at the original error.
+        while True:
+            a = err.args
+            if len(a) >= 1 and isinstance(a[0], OSError):
+                err = a[0]
+            # The error can also be wrapped as args[1]:
+            #    except socket.error as msg:
+            #        raise OSError('socket error', msg).with_traceback(sys.exc_info()[2])
+            elif len(a) >= 2 and isinstance(a[1], OSError):
+                err = a[1]
+            else:
+                break
+        filter_error(err)
+        raise
+    # XXX should we catch generic exceptions and look for their
+    # __cause__ or __context__?
+    finally:
+        socket.setdefaulttimeout(old_timeout)
diff --git a/Lib/test/test_httplib.py b/Lib/test/test_httplib.py
index 6b7a9dedf1..e95487bcd4 100644
--- a/Lib/test/test_httplib.py
+++ b/Lib/test/test_httplib.py
@@ -1629,7 +1629,7 @@ class HTTPSTest(TestCase):
         # Default settings: requires a valid cert from a trusted CA
         import ssl
         support.requires('network')
-        with support.transient_internet('self-signed.pythontest.net'):
+        with socket_helper.transient_internet('self-signed.pythontest.net'):
             h = client.HTTPSConnection('self-signed.pythontest.net', 443)
             with self.assertRaises(ssl.SSLError) as exc_info:
                 h.request('GET', '/')
@@ -1639,7 +1639,7 @@ class HTTPSTest(TestCase):
         # Switch off cert verification
         import ssl
         support.requires('network')
-        with support.transient_internet('self-signed.pythontest.net'):
+        with socket_helper.transient_internet('self-signed.pythontest.net'):
             context = ssl._create_unverified_context()
             h = client.HTTPSConnection('self-signed.pythontest.net', 443,
                                        context=context)
@@ -1653,7 +1653,7 @@ class HTTPSTest(TestCase):
     def test_networked_trusted_by_default_cert(self):
         # Default settings: requires a valid cert from a trusted CA
         support.requires('network')
-        with support.transient_internet('www.python.org'):
+        with socket_helper.transient_internet('www.python.org'):
             h = client.HTTPSConnection('www.python.org', 443)
             h.request('GET', '/')
             resp = h.getresponse()
@@ -1667,7 +1667,7 @@ class HTTPSTest(TestCase):
         import ssl
         support.requires('network')
         selfsigned_pythontestdotnet = 'self-signed.pythontest.net'
-        with support.transient_internet(selfsigned_pythontestdotnet):
+        with socket_helper.transient_internet(selfsigned_pythontestdotnet):
             context = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
             self.assertEqual(context.verify_mode, ssl.CERT_REQUIRED)
             self.assertEqual(context.check_hostname, True)
@@ -1699,7 +1699,7 @@ class HTTPSTest(TestCase):
         # We feed a "CA" cert that is unrelated to the server's cert
         import ssl
         support.requires('network')
-        with support.transient_internet('self-signed.pythontest.net'):
+        with socket_helper.transient_internet('self-signed.pythontest.net'):
             context = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
             context.load_verify_locations(CERT_localhost)
             h = client.HTTPSConnection('self-signed.pythontest.net', 443, context=context)
diff --git a/Lib/test/test_imaplib.py b/Lib/test/test_imaplib.py
index ce601565cf..d1e3550868 100644
--- a/Lib/test/test_imaplib.py
+++ b/Lib/test/test_imaplib.py
@@ -10,7 +10,7 @@ import calendar
 import threading
 import socket
 
-from test.support import (reap_threads, verbose, transient_internet,
+from test.support import (reap_threads, verbose,
                           run_with_tz, run_with_locale, cpython_only)
 from test.support import hashlib_helper
 import unittest
@@ -968,16 +968,16 @@ class RemoteIMAPTest(unittest.TestCase):
     imap_class = imaplib.IMAP4
 
     def setUp(self):
-        with transient_internet(self.host):
+        with socket_helper.transient_internet(self.host):
             self.server = self.imap_class(self.host, self.port)
 
     def tearDown(self):
         if self.server is not None:
-            with transient_internet(self.host):
+            with socket_helper.transient_internet(self.host):
                 self.server.logout()
 
     def test_logincapa(self):
-        with transient_internet(self.host):
+        with socket_helper.transient_internet(self.host):
             for cap in self.server.capabilities:
                 self.assertIsInstance(cap, str)
             self.assertIn('LOGINDISABLED', self.server.capabilities)
@@ -986,7 +986,7 @@ class RemoteIMAPTest(unittest.TestCase):
             self.assertEqual(rs[0], 'OK')
 
     def test_logout(self):
-        with transient_internet(self.host):
+        with socket_helper.transient_internet(self.host):
             rs = self.server.logout()
             self.server = None
             self.assertEqual(rs[0], 'BYE', rs)
@@ -999,7 +999,7 @@ class RemoteIMAP_STARTTLSTest(RemoteIMAPTest):
 
     def setUp(self):
         super().setUp()
-        with transient_internet(self.host):
+        with socket_helper.transient_internet(self.host):
             rs = self.server.starttls()
             self.assertEqual(rs[0], 'OK')
 
@@ -1039,24 +1039,24 @@ class RemoteIMAP_SSLTest(RemoteIMAPTest):
             server.logout()
 
     def test_logincapa(self):
-        with transient_internet(self.host):
+        with socket_helper.transient_internet(self.host):
             _server = self.imap_class(self.host, self.port)
             self.check_logincapa(_server)
 
     def test_logout(self):
-        with transient_internet(self.host):
+        with socket_helper.transient_internet(self.host):
             _server = self.imap_class(self.host, self.port)
             rs = _server.logout()
             self.assertEqual(rs[0], 'BYE', rs)
 
     def test_ssl_context_certfile_exclusive(self):
-        with transient_internet(self.host):
+        with socket_helper.transient_internet(self.host):
             self.assertRaises(
                 ValueError, self.imap_class, self.host, self.port,
                 certfile=CERTFILE, ssl_context=self.create_ssl_context())
 
     def test_ssl_context_keyfile_exclusive(self):
-        with transient_internet(self.host):
+        with socket_helper.transient_internet(self.host):
             self.assertRaises(
                 ValueError, self.imap_class, self.host, self.port,
                 keyfile=CERTFILE, ssl_context=self.create_ssl_context())
diff --git a/Lib/test/test_nntplib.py b/Lib/test/test_nntplib.py
index 2a5a0b97ee..8d296818e6 100644
--- a/Lib/test/test_nntplib.py
+++ b/Lib/test/test_nntplib.py
@@ -246,7 +246,7 @@ class NetworkedNNTPTestsMixin:
         def wrap_meth(meth):
             @functools.wraps(meth)
             def wrapped(self):
-                with support.transient_internet(self.NNTP_HOST):
+                with socket_helper.transient_internet(self.NNTP_HOST):
                     meth(self)
             return wrapped
         for name in dir(cls):
@@ -315,7 +315,7 @@ class NetworkedNNTPTests(NetworkedNNTPTestsMixin, unittest.TestCase):
     @classmethod
     def setUpClass(cls):
         support.requires("network")
-        with support.transient_internet(cls.NNTP_HOST):
+        with socket_helper.transient_internet(cls.NNTP_HOST):
             try:
                 cls.server = cls.NNTP_CLASS(cls.NNTP_HOST,
                                             timeout=support.INTERNET_TIMEOUT,
diff --git a/Lib/test/test_robotparser.py b/Lib/test/test_robotparser.py
index 9d4764ece2..a3112b8fdf 100644
--- a/Lib/test/test_robotparser.py
+++ b/Lib/test/test_robotparser.py
@@ -349,7 +349,7 @@ class NetworkTestCase(unittest.TestCase):
     @classmethod
     def setUpClass(cls):
         support.requires('network')
-        with support.transient_internet(cls.base_url):
+        with socket_helper.transient_internet(cls.base_url):
             cls.parser = urllib.robotparser.RobotFileParser(cls.robots_txt)
             cls.parser.read()
 
diff --git a/Lib/test/test_site.py b/Lib/test/test_site.py
index 12e357cd9b..957e7a41d5 100644
--- a/Lib/test/test_site.py
+++ b/Lib/test/test_site.py
@@ -7,6 +7,7 @@ executing have not been removed.
 import unittest
 import test.support
 from test import support
+from test.support import socket_helper
 from test.support import (captured_stderr, TESTFN, EnvironmentVarGuard,
                           change_cwd)
 import builtins
@@ -509,7 +510,7 @@ class ImportSideEffectTests(unittest.TestCase):
         url = license._Printer__data.split()[1]
         req = urllib.request.Request(url, method='HEAD')
         try:
-            with test.support.transient_internet(url):
+            with socket_helper.transient_internet(url):
                 with urllib.request.urlopen(req) as data:
                     code = data.getcode()
         except urllib.error.HTTPError as e:
diff --git a/Lib/test/test_smtpnet.py b/Lib/test/test_smtpnet.py
index b69cd9de62..74a00a9d7c 100644
--- a/Lib/test/test_smtpnet.py
+++ b/Lib/test/test_smtpnet.py
@@ -1,5 +1,6 @@
 import unittest
 from test import support
+from test.support import socket_helper
 import smtplib
 import socket
 
@@ -28,7 +29,7 @@ class SmtpTest(unittest.TestCase):
         context = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
         context.check_hostname = False
         context.verify_mode = ssl.CERT_NONE
-        with support.transient_internet(self.testServer):
+        with socket_helper.transient_internet(self.testServer):
             server = smtplib.SMTP(self.testServer, self.remotePort)
             try:
                 server.starttls(context=context)
@@ -47,14 +48,14 @@ class SmtpSSLTest(unittest.TestCase):
 
     def test_connect(self):
         support.get_attribute(smtplib, 'SMTP_SSL')
-        with support.transient_internet(self.testServer):
+        with socket_helper.transient_internet(self.testServer):
             server = smtplib.SMTP_SSL(self.testServer, self.remotePort)
             server.ehlo()
             server.quit()
 
     def test_connect_default_port(self):
         support.get_attribute(smtplib, 'SMTP_SSL')
-        with support.transient_internet(self.testServer):
+        with socket_helper.transient_internet(self.testServer):
             server = smtplib.SMTP_SSL(self.testServer)
             server.ehlo()
             server.quit()
@@ -64,20 +65,20 @@ class SmtpSSLTest(unittest.TestCase):
         context.check_hostname = False
         context.verify_mode = ssl.CERT_NONE
         support.get_attribute(smtplib, 'SMTP_SSL')
-        with support.transient_internet(self.testServer):
+        with socket_helper.transient_internet(self.testServer):
             server = smtplib.SMTP_SSL(self.testServer, self.remotePort, context=context)
             server.ehlo()
             server.quit()
 
     def test_connect_using_sslcontext_verified(self):
-        with support.transient_internet(self.testServer):
+        with socket_helper.transient_internet(self.testServer):
             can_verify = check_ssl_verifiy(self.testServer, self.remotePort)
             if not can_verify:
                 self.skipTest("SSL certificate can't be verified")
 
         support.get_attribute(smtplib, 'SMTP_SSL')
         context = ssl.create_default_context()
-        with support.transient_internet(self.testServer):
+        with socket_helper.transient_internet(self.testServer):
             server = smtplib.SMTP_SSL(self.testServer, self.remotePort, context=context)
             server.ehlo()
             server.quit()
diff --git a/Lib/test/test_socket.py b/Lib/test/test_socket.py
index a70e28219e..87ae2e127a 100755
--- a/Lib/test/test_socket.py
+++ b/Lib/test/test_socket.py
@@ -1533,7 +1533,7 @@ class GeneralModuleTests(unittest.TestCase):
     def test_idna(self):
         # Check for internet access before running test
         # (issue #12804, issue #25138).
-        with support.transient_internet('python.org'):
+        with socket_helper.transient_internet('python.org'):
             socket.gethostbyname('python.org')
 
         # these should all be successful
diff --git a/Lib/test/test_ssl.py b/Lib/test/test_ssl.py
index dafdb6c080..5d496c6687 100644
--- a/Lib/test/test_ssl.py
+++ b/Lib/test/test_ssl.py
@@ -2246,7 +2246,7 @@ class NetworkedTests(unittest.TestCase):
     def test_timeout_connect_ex(self):
         # Issue #12065: on a timeout, connect_ex() should return the original
         # errno (mimicking the behaviour of non-SSL sockets).
-        with support.transient_internet(REMOTE_HOST):
+        with socket_helper.transient_internet(REMOTE_HOST):
             s = test_wrap_socket(socket.socket(socket.AF_INET),
                                 cert_reqs=ssl.CERT_REQUIRED,
                                 do_handshake_on_connect=False)
@@ -2259,7 +2259,7 @@ class NetworkedTests(unittest.TestCase):
 
     @unittest.skipUnless(socket_helper.IPV6_ENABLED, 'Needs IPv6')
     def test_get_server_certificate_ipv6(self):
-        with support.transient_internet('ipv6.google.com'):
+        with socket_helper.transient_internet('ipv6.google.com'):
             _test_get_server_certificate(self, 'ipv6.google.com', 443)
             _test_get_server_certificate_fail(self, 'ipv6.google.com', 443)
 
diff --git a/Lib/test/test_timeout.py b/Lib/test/test_timeout.py
index c0952c75e9..ac803f5d63 100644
--- a/Lib/test/test_timeout.py
+++ b/Lib/test/test_timeout.py
@@ -20,7 +20,7 @@ def resolve_address(host, port):
     We must perform name resolution before timeout tests, otherwise it will be
     performed by connect().
     """
-    with support.transient_internet(host):
+    with socket_helper.transient_internet(host):
         return socket.getaddrinfo(host, port, socket.AF_INET,
                                   socket.SOCK_STREAM)[0][4]
 
@@ -230,12 +230,12 @@ class TCPTimeoutTestCase(TimeoutTestCase):
 
         # All that hard work just to test if connect times out in 0.001s ;-)
         self.addr_remote = blackhole
-        with support.transient_internet(self.addr_remote[0]):
+        with socket_helper.transient_internet(self.addr_remote[0]):
             self._sock_operation(1, 0.001, 'connect', self.addr_remote)
 
     def testRecvTimeout(self):
         # Test recv() timeout
-        with support.transient_internet(self.addr_remote[0]):
+        with socket_helper.transient_internet(self.addr_remote[0]):
             self.sock.connect(self.addr_remote)
             self._sock_operation(1, 1.5, 'recv', 1024)
 
diff --git a/Lib/test/test_urllib2.py b/Lib/test/test_urllib2.py
index e69ac3e213..cbfa9ba60c 100644
--- a/Lib/test/test_urllib2.py
+++ b/Lib/test/test_urllib2.py
@@ -1,5 +1,6 @@
 import unittest
 from test import support
+from test.support import socket_helper
 from test import test_urllib
 
 import os
@@ -1776,7 +1777,7 @@ class MiscTests(unittest.TestCase):
     @unittest.skipUnless(support.is_resource_enabled('network'),
                          'test requires network access')
     def test_issue16464(self):
-        with support.transient_internet("http://www.example.com/"):
+        with socket_helper.transient_internet("http://www.example.com/"):
             opener = urllib.request.build_opener()
             request = urllib.request.Request("http://www.example.com/")
             self.assertEqual(None, request.data)
diff --git a/Lib/test/test_urllib2net.py b/Lib/test/test_urllib2net.py
index b3a5e8974d..ba4c500e8e 100644
--- a/Lib/test/test_urllib2net.py
+++ b/Lib/test/test_urllib2net.py
@@ -1,5 +1,6 @@
 import unittest
 from test import support
+from test.support import socket_helper
 from test.test_urllib2 import sanepathname2url
 
 import os
@@ -86,7 +87,7 @@ class CloseSocketTest(unittest.TestCase):
         # calling .close() on urllib2's response objects should close the
         # underlying socket
         url = support.TEST_HTTP_URL
-        with support.transient_internet(url):
+        with socket_helper.transient_internet(url):
             response = _urlopen_with_retry(url)
             sock = response.fp
             self.assertFalse(sock.closed)
@@ -159,7 +160,7 @@ class OtherNetworkTests(unittest.TestCase):
 
     def test_urlwithfrag(self):
         urlwith_frag = "http://www.pythontest.net/index.html#frag"
-        with support.transient_internet(urlwith_frag):
+        with socket_helper.transient_internet(urlwith_frag):
             req = urllib.request.Request(urlwith_frag)
             res = urllib.request.urlopen(req)
             self.assertEqual(res.geturl(),
@@ -167,7 +168,7 @@ class OtherNetworkTests(unittest.TestCase):
 
     def test_redirect_url_withfrag(self):
         redirect_url_with_frag = "http://www.pythontest.net/redir/with_frag/"
-        with support.transient_internet(redirect_url_with_frag):
+        with socket_helper.transient_internet(redirect_url_with_frag):
             req = urllib.request.Request(redirect_url_with_frag)
             res = urllib.request.urlopen(req)
             self.assertEqual(res.geturl(),
@@ -175,7 +176,7 @@ class OtherNetworkTests(unittest.TestCase):
 
     def test_custom_headers(self):
         url = support.TEST_HTTP_URL
-        with support.transient_internet(url):
+        with socket_helper.transient_internet(url):
             opener = urllib.request.build_opener()
             request = urllib.request.Request(url)
             self.assertFalse(request.header_items())
@@ -193,7 +194,7 @@ class OtherNetworkTests(unittest.TestCase):
 
         URL = 'http://www.imdb.com' # mangles Connection:close
 
-        with support.transient_internet(URL):
+        with socket_helper.transient_internet(URL):
             try:
                 with urllib.request.urlopen(URL) as res:
                     pass
@@ -223,7 +224,7 @@ class OtherNetworkTests(unittest.TestCase):
                 else:
                     req = expected_err = None
 
-                with support.transient_internet(url):
+                with socket_helper.transient_internet(url):
                     try:
                         f = urlopen(url, req, support.INTERNET_TIMEOUT)
                     # urllib.error.URLError is a subclass of OSError
@@ -265,7 +266,7 @@ class TimeoutTest(unittest.TestCase):
     def test_http_basic(self):
         self.assertIsNone(socket.getdefaulttimeout())
         url = support.TEST_HTTP_URL
-        with support.transient_internet(url, timeout=None):
+        with socket_helper.transient_internet(url, timeout=None):
             u = _urlopen_with_retry(url)
             self.addCleanup(u.close)
             self.assertIsNone(u.fp.raw._sock.gettimeout())
@@ -273,7 +274,7 @@ class TimeoutTest(unittest.TestCase):
     def test_http_default_timeout(self):
         self.assertIsNone(socket.getdefaulttimeout())
         url = support.TEST_HTTP_URL
-        with support.transient_internet(url):
+        with socket_helper.transient_internet(url):
             socket.setdefaulttimeout(60)
             try:
                 u = _urlopen_with_retry(url)
@@ -285,7 +286,7 @@ class TimeoutTest(unittest.TestCase):
     def test_http_no_timeout(self):
         self.assertIsNone(socket.getdefaulttimeout())
         url = support.TEST_HTTP_URL
-        with support.transient_internet(url):
+        with socket_helper.transient_internet(url):
             socket.setdefaulttimeout(60)
             try:
                 u = _urlopen_with_retry(url, timeout=None)
@@ -296,7 +297,7 @@ class TimeoutTest(unittest.TestCase):
 
     def test_http_timeout(self):
         url = support.TEST_HTTP_URL
-        with support.transient_internet(url):
+        with socket_helper.transient_internet(url):
             u = _urlopen_with_retry(url, timeout=120)
             self.addCleanup(u.close)
             self.assertEqual(u.fp.raw._sock.gettimeout(), 120)
@@ -306,7 +307,7 @@ class TimeoutTest(unittest.TestCase):
     @skip_ftp_test_on_travis
     def test_ftp_basic(self):
         self.assertIsNone(socket.getdefaulttimeout())
-        with support.transient_internet(self.FTP_HOST, timeout=None):
+        with socket_helper.transient_internet(self.FTP_HOST, timeout=None):
             u = _urlopen_with_retry(self.FTP_HOST)
             self.addCleanup(u.close)
             self.assertIsNone(u.fp.fp.raw._sock.gettimeout())
@@ -314,7 +315,7 @@ class TimeoutTest(unittest.TestCase):
     @skip_ftp_test_on_travis
     def test_ftp_default_timeout(self):
         self.assertIsNone(socket.getdefaulttimeout())
-        with support.transient_internet(self.FTP_HOST):
+        with socket_helper.transient_internet(self.FTP_HOST):
             socket.setdefaulttimeout(60)
             try:
                 u = _urlopen_with_retry(self.FTP_HOST)
@@ -326,7 +327,7 @@ class TimeoutTest(unittest.TestCase):
     @skip_ftp_test_on_travis
     def test_ftp_no_timeout(self):
         self.assertIsNone(socket.getdefaulttimeout())
-        with support.transient_internet(self.FTP_HOST):
+        with socket_helper.transient_internet(self.FTP_HOST):
             socket.setdefaulttimeout(60)
             try:
                 u = _urlopen_with_retry(self.FTP_HOST, timeout=None)
@@ -337,7 +338,7 @@ class TimeoutTest(unittest.TestCase):
 
     @skip_ftp_test_on_travis
     def test_ftp_timeout(self):
-        with support.transient_internet(self.FTP_HOST):
+        with socket_helper.transient_internet(self.FTP_HOST):
             u = _urlopen_with_retry(self.FTP_HOST, timeout=60)
             self.addCleanup(u.close)
             self.assertEqual(u.fp.fp.raw._sock.gettimeout(), 60)
diff --git a/Lib/test/test_urllibnet.py b/Lib/test/test_urllibnet.py
index 422d529a70..28680aa6b2 100644
--- a/Lib/test/test_urllibnet.py
+++ b/Lib/test/test_urllibnet.py
@@ -1,5 +1,6 @@
 import unittest
 from test import support
+from test.support import socket_helper
 
 import contextlib
 import socket
@@ -27,7 +28,7 @@ class URLTimeoutTest(unittest.TestCase):
         self.addCleanup(urllib.request.urlcleanup)
 
         domain = urllib.parse.urlparse(support.TEST_HTTP_URL).netloc
-        with support.transient_internet(domain):
+        with socket_helper.transient_internet(domain):
             f = urllib.request.urlopen(support.TEST_HTTP_URL)
             f.read()
 
@@ -56,7 +57,7 @@ class urlopenNetworkTests(unittest.TestCase):
     @contextlib.contextmanager
     def urlopen(self, *args, **kwargs):
         resource = args[0]
-        with support.transient_internet(resource):
+        with socket_helper.transient_internet(resource):
             r = urllib.request.urlopen(*args, **kwargs)
             try:
                 yield r
@@ -98,7 +99,7 @@ class urlopenNetworkTests(unittest.TestCase):
     def test_getcode(self):
         # test getcode() with the fancy opener to get 404 error codes
         URL = self.url + "XXXinvalidXXX"
-        with support.transient_internet(URL):
+        with socket_helper.transient_internet(URL):
             with self.assertWarns(DeprecationWarning):
                 open_url = urllib.request.FancyURLopener().open(URL)
             try:
@@ -156,7 +157,7 @@ class urlretrieveNetworkTests(unittest.TestCase):
     @contextlib.contextmanager
     def urlretrieve(self, *args, **kwargs):
         resource = args[0]
-        with support.transient_internet(resource):
+        with socket_helper.transient_internet(resource):
             file_location, info = urllib.request.urlretrieve(*args, **kwargs)
             try:
                 yield file_location, info